I've always approached practice with the thought in mind to hit the smallest target possible.
Our military unit used 3" x 5" blank notecards as our shooting target area with our handguns. On the range, we would fire box after box after box after box of ammo at those little notecards. We fire from all positions. We'd fire after having just run three miles, literally stopping at our respective lanes, draw and fire. We'd have blindfolds on, partners would yank them off, and we'd have to draw and fire at that little note card.
Our CO's rational was that we needed to keep our groups in a three-inch by five-inch range no matter what condition you were in physically, mentally or emotionally. We spent something like a full-week doing nothing but dry firing at those notecards before he issued us live ammo.
It worked. In fact, all these years later, I still only shoot at 3 x 5 notecards for my handgun shooting.
If you are taken by surprise, you will have little or no way to use firearms training effectively. Everything will fall apart and you will be very lucky to bring your weapon into play at all.
I could not possibly disagree more. Our platoon had a motto that went, "You Train Train Train so that you will always React React React because if you have to stop and Think Think Think, all you will do is Die Die Die."
And in our line of work, we were surprised far more often than we cared to be.
You train so that you will react accordingly and appropriately. Otherwise, what's the point of training at all?
Training is expensive. If it didn't work and pay off, I doubt so many professional gun-toters would bother with it.